stuart



(No Model.) a Sheets-Sheen 1.

0. 0. STUART. BELT TIGHTENER.

No. 548,404. Patented Oct. 22, 1895.

ANDREW IGHANAM. FNOTO-U'IHQWASMKOYGX D C (N0 Modi.) 3 Sheets-Sheet 2. O.G. STUART.

BELT TIGHTENER. No. 548,404. Patented Oct. 22, 1895 AN mmasnmmmdfombi'wnsmuamlva (No Model.) 3 SheetsSheet 3.

0. O. STUART.

BELT TIGHTENER.

No. 548,404. Patented Oct. 22, 1895.

AN DREW KER-AHA".YHOTO'UTNQWASHIHGTOKEC.

UNITED STATES PATENT Orricn.

CHARLES C. STUART, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE GLEN COVEMACHINE COMPANY, LIMITED, OF SAME PLACE.

BELT-TlGHTiZNER.

SPECIFICATION forming part of Letters Patent No. 548,404, dated October22, 1895.

Application filed March 25, 1894. semi No. 504,764. (No model.)

To all whom it may concern.-

Be it known that I, CHARLES C. STUART, of Brooklyn, in the county ofKings and State of New York, have invented a new and useful 5Improvement in Belt-Tightening Mechanism for Surfacing-Machines, ofwhich the following is a specification.

My invention relates to an improvement in belt-tightening mechanism forsurfacing-machines, in which a cutter-head located in an adjustableframe is driven by a belt from a driving-pulley located on a supportindependent of the adjustable frame.

The object is to provide means for setting and automatically maintainingthe belt at the tension to which it has been set during the variousadjustments of the cutter-headcarrying frame.

A practical embodiment of my invention is represented in theaccompanying drawings, in which Figure l is a View in side elevation ofso much of a surfacing-machine as will suflice to show the practicaloperation of the belt adjusting and tightening mechanism. Fig. 2 is avertical longitudinal section through the same. Fig. 3 is ahorizontalsection showing the operating mechanism for tightening the belt in topplan, and Figsnt, 5, and 6 are enlarged views in detail of parts of thebelttightening mechanism.

The bed-frame of the machine is denoted by A.

a represents the end frame uprising from the bed frame A and serving, inconjunction with a corresponding end frame, (not shown) to form guidesfor the vertically-movable upper frame 13, which carries the topfeed-rollers and the upper cutter-head O. The frame (1 also serves as asupport for two of the four similar screws I), located one at eachcorner of the vertically-movable frame B, for the purpose of adjustingit toward and away from the bed-frame A to suit lumber and timber ofvarying thicknesses. The

screws D are operated by means of vertical shafts E, geared withgear-wheels on the screws, the shafts E being driven by a horizontalshaft 13, geared with the shafts E by miter-gear.

The belt G, which drives the cutter-head O in the vertically-adjustableupper frame, extends from and is driven by a drive-pulley H, mounted inthe lower frame A. It is to the tightening and maintaining the tensionof the drive-belt G under the various adjustments of the frame 13 thatmy present invention is more particularly directed. To accomplish this,it is obviously necessary that the tightening and loosening of the beltshall correspond with the movement of the adjustable frame B, whichtends to decrease or increase the tension on the belt, and I havetherefore placed the belt tightening and loosening mechanism under thecontrol of the particular mechanism which is employed to elevate andlower the said upper frame.

A transverse shaft I, continuously driven from the shaft h, on which thedrive-pulleys H are fixed, is journaled nearone end in ahorizontally-rocking bearing 1', and is provided at its opposite endwith friction-pulleys t" and i for engaging either the interior face kof a. friction-pulley K or the exterior surface of the inner rim is onthe said pulley K to rotate said pulley K in the one direction or theother, as may be desired. The shaft I is swung to bring itsfriction-pulleys into engagement with the inner or outer portions ofsaid pulley K by means of a rod L, connected to a sliding bearing 2' ofsaid shaft I, and also to a rockshaft l under the control of ahand-1ever Z The shaft 10 on which the pulley K is fixed, gears with theshaft F for operating the upright shafts E, and hence the screw D, toadjust the frame B. The shaft F projects past the shaft k and isprovided with a bevelgearf, in mesh with a corresponding gear m on atransverse shaft M, mounted in suitable hearings in the bed-frame. Atits opposite ends the shaft M is provided with bevel-gears m, arrangedto mesh with corresponding gears 07. on screws N, held at their lowerends in suitable bearings 72., so as to permit them to rotate freelywithout themselves advancing longitudinally. lhe bearings n are fixed torocking frames 0, hinged on the shaft M and provided with elongatedslots 0, through which clamp-screws 0 extend into the bedframe to holdthe rocking supporting-frame O in the desired rocked adjustment. Fixedto the face of the frame 0 is a way or tonguepiece P, on which a slide Qis arranged to travel. The slide Q isFprovided with a pivot q, on whicha loose belt-tightening pulley q is mounted. The rocking frames 0 andthe parts which they carry are quite similar upon opposite sides of themachine, as clearly indicated. in Fig. 3.

The screws N engage in nuts R, fixed to the slides Q, so that as thescrews N are rotated in the one direction or the other the nuts R, andhence the slides Q. to which they are fixed, and the pulleys q, carriedby the slides, Will be caused to travel along the way or tongue Pin theone direction or the other to take up or let out the belt G.

In operation the belt G is first adjusted to the desired tension byrocking the frame 0 on the shaft M to increase or decrease the tensionon the belt, and after this adjustment is obtained the tension will beautomatically maintained by the operation of the screws N, under thecontrol of the mechanism which actuates the movable upper frame to varyits adjustment relatively to the lower frame1. a, when the shaft I isdrawn into position to rotate the pulley K in a direction to move theupper frame away from the lower frame, and hence increase the tensionupon the belt G, the shaft F will at the same time rotate the shaft M,and hence the screws N, in a direction to lower the tension-pulleys q,and hence slackening the belt G,the amount of slackening being exactlyproportioned to the amount of take-up caused by the elevation of theupper frame. When, on the other hand, the shaft I is moved in adirection to actuate the pulley K to lower the upper frame, it willimpart to the screws N the reverse movement, and hence will force thetightening-pulleys q to.- ward the belt G to take up just that; amountwhich is slackened by the lowering of said upper frame.

At any time when the belt becomes stretched, so that the normal tensionis less than what is desired, the proper tension to be maintained may beat once obtained by rocking the frames 0 in the one direction or theother, as hereinabove set forth.

It is obvious that slight changes might be to limit myself strictly tothe structure and arrangement herein shown and described; but

What I claim is 1. The combination with an adjustable up per frame,means for actuating it, a cutter carried by said frame, adriving pulleymount ed independently of said cutter carrying frame and a beltconnecting said driving pulley with said cutter spindle, of a rockingframe and belttightening mechanism carried by said rocking frame andunder the control 5 of the movable frame actuating mechanism to maintaina uniform tension upon the belt during the movements of said upperframe, substantially as set forth.

2. The combination with a vertically adjustable upper frame, the cuttercarried thereby, the lower frame, a driving pulley mounted therein and abelt connecting said driving pulley and cutter spindle, of mechanism foradjusting the upper frame including a shaft extending along the bedframe, a slide carrying a belt tightening pulley, a screw for operatingthe slide and gear under the control of said shaft, extending along thebed frame, for operating said screw, substantially as set forth.

3. The combination, with a lower frame, the drive pulley, the adjustableupper frame, the cutter carried thereby, and the belt connecting thedrive pulley with said cutter spindle, of mechanism for adjusting theupper tending along the bed frame, a transverse shaft in gear with saidshaft extending along the bed frame, a slide carrying a belt tighteningpulley and mounted to move toward and away from the belt, a screwengaged with said slide and gear connecting said transverse shaftv withthe screw, substantially as set forth.

4. The combination with a movable upper frame, the rotary part carriedthereby, the drive pulley and the belt connecting said rotary part withthe driving pulley, of mechanism for actuating the upper frame, arocking frame, a slide carrying a belt tightening puiley and mounted onsaid rocking frame and mechanism for moving the said pulley-carryingslide under the control of the upper frame actuating mechanism,substantially as set forth.

5. The combination with the driving belt, of a transverse shaft,arocking frame hinged on said shaft, means for locking the frame in adesired rocked adjustment, a slide mounted on said rocking frame andcarrying a belttightening pulley, mechanism connecting the transverseshaft and slide for adjusting the slide along the support and means foractuating the shaft, substantially as set forth.

CHARLES C. STUART.

Witnesses:

IRENE B. DECKER, FREDK. HAYNES.

